Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758387Ab1FPW34 (ORCPT ); Thu, 16 Jun 2011 18:29:56 -0400 Received: from mx1.redhat.com ([209.132.183.28]:65028 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755776Ab1FPW23 (ORCPT ); Thu, 16 Jun 2011 18:28:29 -0400 From: Glauber Costa To: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Rik van Riel , Jeremy Fitzhardinge , Peter Zijlstra , Avi Kivity , Anthony Liguori , Eric B Munson Subject: [PATCH v2 3/7] KVM-HV: KVM Steal time implementation Date: Thu, 16 Jun 2011 18:20:52 -0400 Message-Id: <1308262856-5779-4-git-send-email-glommer@redhat.com> In-Reply-To: <1308262856-5779-1-git-send-email-glommer@redhat.com> References: <1308262856-5779-1-git-send-email-glommer@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5989 Lines: 191 To implement steal time, we need the hypervisor to pass the guest information about how much time was spent running other processes outside the VM. This is per-vcpu, and using the kvmclock structure for that is an abuse we decided not to make. In this patchset, I am introducing a new msr, KVM_MSR_STEAL_TIME, that holds the memory area address containing information about steal time This patch contains the hypervisor part for it. I am keeping it separate from the headers to facilitate backports to people who wants to backport the kernel part but not the hypervisor, or the other way around. Signed-off-by: Glauber Costa CC: Rik van Riel CC: Jeremy Fitzhardinge CC: Peter Zijlstra CC: Avi Kivity CC: Anthony Liguori CC: Eric B Munson --- arch/x86/include/asm/kvm_host.h | 8 +++++ arch/x86/include/asm/kvm_para.h | 4 ++ arch/x86/kvm/x86.c | 60 +++++++++++++++++++++++++++++++++++++-- 3 files changed, 69 insertions(+), 3 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index fc38eca..5dce014 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -388,6 +388,14 @@ struct kvm_vcpu_arch { unsigned int hw_tsc_khz; unsigned int time_offset; struct page *time_page; + + struct { + u64 msr_val; + gpa_t stime; + struct kvm_steal_time steal; + u64 this_time_out; + } st; + u64 last_guest_tsc; u64 last_kernel_ns; u64 last_tsc_nsec; diff --git a/arch/x86/include/asm/kvm_para.h b/arch/x86/include/asm/kvm_para.h index ac306c4..0341e61 100644 --- a/arch/x86/include/asm/kvm_para.h +++ b/arch/x86/include/asm/kvm_para.h @@ -45,6 +45,10 @@ struct kvm_steal_time { __u32 pad[6]; }; +#define KVM_STEAL_ALIGNMENT_BITS 5 +#define KVM_STEAL_VALID_BITS ((-1ULL << (KVM_STEAL_ALIGNMENT_BITS + 1))) +#define KVM_STEAL_RESERVED_MASK (((1 << KVM_STEAL_ALIGNMENT_BITS) - 1 ) << 1) + #define KVM_MAX_MMU_OP_BATCH 32 #define KVM_ASYNC_PF_ENABLED (1 << 0) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 6645634..10fe028 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -797,12 +797,12 @@ EXPORT_SYMBOL_GPL(kvm_get_dr); * kvm-specific. Those are put in the beginning of the list. */ -#define KVM_SAVE_MSRS_BEGIN 8 +#define KVM_SAVE_MSRS_BEGIN 9 static u32 msrs_to_save[] = { MSR_KVM_SYSTEM_TIME, MSR_KVM_WALL_CLOCK, MSR_KVM_SYSTEM_TIME_NEW, MSR_KVM_WALL_CLOCK_NEW, HV_X64_MSR_GUEST_OS_ID, HV_X64_MSR_HYPERCALL, - HV_X64_MSR_APIC_ASSIST_PAGE, MSR_KVM_ASYNC_PF_EN, + HV_X64_MSR_APIC_ASSIST_PAGE, MSR_KVM_ASYNC_PF_EN, MSR_KVM_STEAL_TIME, MSR_IA32_SYSENTER_CS, MSR_IA32_SYSENTER_ESP, MSR_IA32_SYSENTER_EIP, MSR_STAR, #ifdef CONFIG_X86_64 @@ -1480,6 +1480,34 @@ static void kvmclock_reset(struct kvm_vcpu *vcpu) } } +static void record_steal_time(struct kvm_vcpu *vcpu) +{ + u64 delta; + + if (vcpu->arch.st.stime && vcpu->arch.st.this_time_out) { + + if (unlikely(kvm_read_guest(vcpu->kvm, vcpu->arch.st.stime, + &vcpu->arch.st.steal, sizeof(struct kvm_steal_time)))) { + + vcpu->arch.st.stime = 0; + return; + } + + delta = (get_kernel_ns() - vcpu->arch.st.this_time_out); + + vcpu->arch.st.steal.steal += delta; + vcpu->arch.st.steal.version += 2; + + if (unlikely(kvm_write_guest(vcpu->kvm, vcpu->arch.st.stime, + &vcpu->arch.st.steal, sizeof(struct kvm_steal_time)))) { + + vcpu->arch.st.stime = 0; + return; + } + } + +} + int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data) { switch (msr) { @@ -1562,6 +1590,23 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data) if (kvm_pv_enable_async_pf(vcpu, data)) return 1; break; + case MSR_KVM_STEAL_TIME: + vcpu->arch.st.msr_val = data; + + if (!(data & KVM_MSR_ENABLED)) { + vcpu->arch.st.stime = 0; + break; + } + + if (data & KVM_STEAL_RESERVED_MASK) + return 1; + + vcpu->arch.st.this_time_out = get_kernel_ns(); + vcpu->arch.st.stime = data & KVM_STEAL_VALID_BITS; + record_steal_time(vcpu); + + break; + case MSR_IA32_MCG_CTL: case MSR_IA32_MCG_STATUS: case MSR_IA32_MC0_CTL ... MSR_IA32_MC0_CTL + 4 * KVM_MAX_MCE_BANKS - 1: @@ -1847,6 +1892,9 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata) case MSR_KVM_ASYNC_PF_EN: data = vcpu->arch.apf.msr_val; break; + case MSR_KVM_STEAL_TIME: + data = vcpu->arch.st.msr_val; + break; case MSR_IA32_P5_MC_ADDR: case MSR_IA32_P5_MC_TYPE: case MSR_IA32_MCG_CAP: @@ -2158,6 +2206,8 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) kvm_migrate_timers(vcpu); vcpu->cpu = cpu; } + + record_steal_time(vcpu); } void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) @@ -2165,6 +2215,7 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) kvm_x86_ops->vcpu_put(vcpu); kvm_put_guest_fpu(vcpu); kvm_get_msr(vcpu, MSR_IA32_TSC, &vcpu->arch.last_guest_tsc); + vcpu->arch.st.this_time_out = get_kernel_ns(); } static int is_efer_nx(void) @@ -2477,7 +2528,8 @@ static void do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, (1 << KVM_FEATURE_NOP_IO_DELAY) | (1 << KVM_FEATURE_CLOCKSOURCE2) | (1 << KVM_FEATURE_ASYNC_PF) | - (1 << KVM_FEATURE_CLOCKSOURCE_STABLE_BIT); + (1 << KVM_FEATURE_CLOCKSOURCE_STABLE_BIT) | + (1 << KVM_FEATURE_STEAL_TIME); entry->ebx = 0; entry->ecx = 0; entry->edx = 0; @@ -6200,6 +6252,8 @@ int kvm_arch_vcpu_reset(struct kvm_vcpu *vcpu) kvmclock_reset(vcpu); + vcpu->arch.st.stime = 0; + kvm_clear_async_pf_completion_queue(vcpu); kvm_async_pf_hash_reset(vcpu); vcpu->arch.apf.halted = false; -- 1.7.3.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/